But the estimates are given in terms of the projected number of trips or boardings, rather than in terms of people. That makes figuring out the number of people who will be riding rail a little harder.

So where did “two in 100” come from?

Listen to the full commercial here:

The Cayetano campaign said that it derived the “two in 100” figure from tables 3-12 and 3-18 of the FEIS. Chapter 3 of the FEIS describes the anticipated effect of the rail project on transportation. Here’s the campaign’s official response to our question about how they found 2 percent:

The Final EIS Table 3-12 shows that only 7.4 percent of Hawai‘i residents trips will be made using transit in 2030. Of these, Table 3-18 shows us that 25.7 percent of boardings are rail and 74.3 percent by bus. Since the trips are not analyzed in the Final EIS, one can only infer from the data that 25.7 percent of the 7.4 percent, or 1.9 percent, or 2 in 100, is by train.

If you take 25.7 percent of 7.4, the math checks out. But does that figure actually describe the percentage of Hawaii residents who will use rail?

The units in the figures used don’t line up. Part of the problem is the campaign is mixing two very different things — trips are different than boardings and one total includes tourists and the other doesn’t.

First, the numbers cited in Table 3-12 refer to trips, while the numbers in Table 3-18 refer to boardings. The FEIS explains that the term “trip” is defined differently from “boarding” because the former includes transfers and the latter does not.

Second, the percentage 7.4 from Table 3-12 refers only to residents, while the percentage 25.7 from tables 3-18 and 3-19 refers to both residents and tourists.

According to Cliff Slater, a vocal anti-rail activist and the transportation expert for the Cayetano campaign, these differences weren’t taken into account in the campaign’s calculations because those were the only relevant figures he could find in the FEIS.

The ad’s message — “two out of 100 people will take rail” — sounds to us and the causal listener that very few island residents will use the system. But nowhere in the campaign’s calculation is the city’s population taken into account.

Slater acknowledged that the number of trips doesn’t translate into population.

“One of the problems is that the city gives you numbers where you can’t compare,” he said.

It’s worth noting that the city has also mixed up terms used in the FEIS. Earlier this year, Civil Beat fact checked Mayor Peter Carlisle for confusing car trips and cars.

So what would happen if you simply divided the number of daily rail boardings, 116,300, by the population? According to Scott Ishikawa from the Honolulu Authority on Rail Transit (HART), one boarding is equivalent to one person. That would mean about 10 percent of residents would be riding the rail, significantly more than the campaign ad would have us believe.

But a person will likely board the train more than once per day. Thus, it’s not exactly clear from the FEIS how many people will be riding rail each day.

Switching from Bus to Train

The commercial also says that half of those who ride rail will be current bus riders, according to the city and the FTA.

The Cayetano campaign provided this explanation:

“Table 3-18 also shows us that in 2030, the rail/bus project is only adding 56,000 daily trips from what it would be from bus riders only (No Build). Table 3-12 shows that automobile trips change from No Build to the rail/bus Project is -48,200. We assume that 25.7 percent (see above), or 12,400, go by rail and the rest by bus. Thus the additional transit trips will come for the most part from bus riders. It is the norm for half of the new riders to come from bus riders and quite a few from former car passengers.

In other words, the campaign assumes that because 74.3 percent of all transit boardings island wide in 2030 are on the bus, then 74.3 percent of all new transit boardings created by the rail would also be on the bus. But the island wide ratio can’t be applied to just one group of people — those trading cars for public transit.

Trips and boardings are also being mixed up. The number 48,200 refers to trips by residents while 25.7 percent refers to boardings by residents and tourists.

But according to Ishikawa, the city agrees that most people who ride the rail will be existing bus riders.

“Bus ridership will make up a sizable portion of the rail ridership,” Ishikawa said, noting also that public transit ridership as a whole is expected to increase if the rail system is built.

Below are images of the tables so you can examine them yourself. You can also view them in context by reading Chapter 3 of the FEIS.

Table 3-12 provides estimates of how many trips are taken each day on Oahu and by which modes of transportation, such as public transit, bicycle, or car. Estimates were provided for 2007, 2030 with rail, and 2030 without rail.

Table 3-18 shows estimates of how many people rode or will ride public transit in terms of trips and boardings.

Table 3-19 is also helpful because it breaks down public transit usage by type.

BOTTOM LINE: The ad leaves the impression that only 2 percent of Oahu’s population will ride rail. But the campaign, whose advisors include engineers and transit planners, compared apples and oranges in order to get a sound bite. Trips are not boardings, people and trips don’t equate. But on the other hand, the city projects that most of those using rail will be existing bus riders. The ad said half would be bus riders. Since the claim contains elements of truth as well as some facts that can’t support the claim, we give this one a HALF TRUE.